Moss cleaning method for sedimentation tank

Abstract

The invention relates to the technical field of moss cleaning in sewage treatment, and discloses a method for cleaning moss in a sedimentation tank, which comprises the following steps: S1, pretreating moss, and converting the moss into a state convenient to remove by physical and chemical methods; s2, spraying treatment: spraying the moss with reclaimed water containing sodium hypochloride in a temperature range of 20-30 DEG C; s3, performing ultraviolet irradiation, namely performing ultraviolet irradiation on the obtained first moss; s4, inhibiting the growth of moss, namely performing post-treatment on the second moss to inhibit the growth of the second moss; s5, waste is cleaned, moss residues, cleaning agents and other waste generated in the cleaning process are cleaned in time, influences of the residues on water quality are avoided, and moss is prevented from growing again. Through a physical and chemical combined mode, loose moss in the sedimentation tank is effectively removed firstly, then a solution containing sodium hypochloride is used for spraying the moss, it is ensured that all moss patches are in uniform contact, and the ideal chemical cleaning effect is achieved.

Description

Technical Field

[0001] The invention relates to the technical field of moss cleaning in a sedimentation tank, and in particular to a moss cleaning method for a sedimentation tank. Background Art

[0002] A sedimentation tank is a structure that uses sedimentation to remove suspended matter from water. It is a type of water purification equipment that uses the natural sedimentation of water or the effect of coagulation and sedimentation to remove suspended matter from water. Currently, in the field of water management and environmental protection, sedimentation tanks are widely used as key facilities for water treatment and sewage treatment, and mainly remove suspended matter, solid particles and nutrients from water through gravity sedimentation. However, after a sedimentation tank has been used for a long time, aquatic plants such as moss are extremely likely to grow on the edge of the table (on the water surface) of the sedimentation tank, and they are prone to overgrowth, which can have a negative impact on the water quality and ecological environment of the water after sedimentation treatment. This not only affects the treatment efficiency of the sedimentation tank, but also easily leads to problems such as hypoxia and eutrophication of the water body, thereby damaging the aquatic ecosystem and reducing the treatment effect of the sedimentation tank.

[0003] At the same time, since moss is a bryophyte, it often attaches to the surface of objects and spreads and grows. Moss is emerald green in color, and its stems are as thin as silk. It can attach to dark and humid places such as rocks, pools, roof tiles, dilapidated walls, wetlands, etc. like hair. It will also compete with aquatic plants and other algae for nutrients, excessively consume nutrients in the water body, destroy the normal metabolism of substances in the water body after sedimentation treatment, make the water body thin, and inhibit the growth of aquatic plants. The periodic growth of plankton is destroyed, resulting in an imbalance of algae in the water body; at the same time, the dead moss is blown to the corners of the pool by the wind or sinks to the bottom to rot, which is easy to emit a foul smell. In the process of decomposition, it will also consume dissolved oxygen in the water and produce many toxic and harmful substances, resulting in a decrease in dissolved oxygen in the water body, an increase in harmful substances such as ammonia nitrogen, nitrite, and hydrogen sulfide, and deteriorating the water quality.

[0004] At present, there are mainly the following methods for cleaning moss on the surface of sedimentation tanks: Physical cleaning method: Physical cleaning methods include manual cleaning. Although these methods can remove moss to a certain extent, their efficiency is low and they can easily cause secondary pollution of the water body.

[0005] Chemical cleaning method: remove moss by using strong acid and strong alkali; although these methods are effective, they often have adverse effects on the water environment, leading to an increase in harmful substances in the water, and easily causing secondary pollution to the water after sedimentation, reducing the efficiency of sewage treatment and affecting the survival of aquatic organisms.

[0006] Therefore, how to deal with the moss on the sedimentation tank is a technical problem that technicians need to solve. Summary of the invention

[0007] In view of the deficiencies in the prior art, the present invention provides a moss cleaning method for a sedimentation tank, which is used to solve the problems raised in the above-mentioned background technology.

[0008] To achieve the above objectives, the present invention provides a method for cleaning moss in a sedimentation tank, comprising the following steps: S1. Pre-treating the moss on the sedimentation tank, wherein the moss is attached to the overflow weir of the sedimentation tank, and the pre-treating comprises: converting the moss on the sedimentation tank into a state that is easy to remove by a physical method or a chemical method; the sedimentation tank is a vertical flow sedimentation tank, the plane of the tank body is circular or square, and the wastewater is discharged into the tank from top to bottom through a water inlet pipe located in the center of the sedimentation tank; S2. After the pretreatment, spraying the moss on the sedimentation tank, the spraying treatment comprising: spraying the overflow weir of the sedimentation tank with reclaimed water containing sodium hypochlorite at a temperature range of 20° C. to obtain a first sewage solution, which is a primary clarified solution of domestic wastewater after sedimentation treatment, mixed with suspended matter and hypochlorous acid solution; S3, after the first preset time period of spraying is completed, the secondary sewage solution is subjected to ultraviolet irradiation to obtain a second sewage solution, wherein the second sewage solution is a secondary clarified solution mixed with suspended matter and moss residue after the primary clarified solution is decomposed by light; S4, post-treating the second sewage solution to obtain a third sewage solution, wherein the third sewage solution is a clean clarified solution mixed with a variety of residual wastes after the intermediate clarified solution is post-treated; S5. Cleaning the third sewage solution to obtain clean water. The cleaning includes: timely collecting moss residues generated during the cleaning process, and short-term isolating or physically filtering the treated third sewage solution.

[0009] In one implementation method, the physical method includes: using a mechanical brush or a high-pressure water gun to perform preliminary cleaning around and on the outer wall of the overflow weir to remove loose moss on the surface; the chemical method includes: using an acidic or alkaline solution combined with a cleaning agent to adjust the pH value until it is adjusted to a range suitable for moss removal, thereby promoting the rupture and shedding of moss cells.

[0010] In one implementation method, the use of reclaimed water containing sodium hypochlorite to spray the edge of the sedimentation tank includes the following steps: The intermediate water containing the sodium hypochlorite solution is sequentially and rotationally sprayed on the surface of the overflow weir along one of the starting points of the overflow weir; wherein the spraying time is controlled within 15 minutes to 30 minutes.

[0011] In one embodiment, the sodium hypochlorite concentration of the sodium hypochlorite-containing reclaimed water is 0.1% to 0.5%.

[0012] In one implementation method, the secondary sewage solution is subjected to ultraviolet irradiation, comprising: The ultraviolet lamp is kept about 30 cm to 50 cm away from the moss surface, wherein the irradiation time of the ultraviolet lamp is controlled within 30 min to 60 min, and the wavelength of the ultraviolet lamp is 200 nm to 280 nm.

[0013] In one implementation method, the second sewage solution is post-treated, comprising: A biological inhibitor of a specific concentration is evenly sprayed on the moss treatment area of ​​the overflow weir, and the nitrogen-phosphorus ratio of the water body is reduced. After a third preset time period, aquatic plants with inhibitory effects are added.

[0014] In one implementation method, the bioinhibitor includes any one or more of the following: alginate, photosynthetic bacteria and lactic acid bacteria; the aquatic plant includes any one or more of the following: water hyacinth, foxtail, algae reed and cattail.

[0015] In an implementation method, after step S5, step S6 is further included, and step S6 includes: After a second preset time, the thickness of the moss on the overflow weir is detected, and if the thickness of the moss is greater than a reference thickness, reprocessing is performed; The re-treatment includes using professional equipment or manually checking the moss coverage on the overflow weir to determine the moss coverage rate. When the moss coverage rate is greater than 30%, spraying or ultraviolet irradiation is performed again; wherein, the moss coverage rate refers to.

[0016] In an implementation method, after step S6, step S7 is further included, and step S7 includes the following steps: Use water quality regulators to adjust the pH value and dissolved oxygen concentration of water bodies; According to the pH value and dissolved oxygen concentration of the water body, ensure that the dissolved oxygen content in the water body is moderate by supplementing oxygen or adjusting the water flow, and establish a regular inspection and maintenance mechanism to regularly detect, clean and prevent moss.

[0017] The present invention has the following beneficial effects: 1. The present invention forms a multi-level moss cleaning mechanism through four systematic steps, including pretreatment, spray treatment, ultraviolet irradiation and biological inhibition. Through a combination of physical and chemical methods, the loose moss in the sedimentation tank is first effectively removed, and then the moss is sprayed with a solution containing sodium hypochlorite to ensure that each moss patch is evenly contacted to achieve an ideal chemical cleaning effect. In addition, ultraviolet irradiation further destroys the structure of moss cells and enhances the removal effect. Ultimately, this series of treatments can not only significantly reduce the biomass of moss, but also increase the light transmittance and oxygen content of the water body, thereby improving water quality and promoting the healthy development of the water ecology.

[0018] 2. The present invention can effectively inhibit the regeneration of moss by introducing biological inhibitors and aquatic plants in the post-treatment step without causing negative impact on the water body. Biological inhibitors such as alginate, photosynthetic bacteria and lactic acid bacteria are all natural substances with good environmental compatibility and will not pollute water sources. At the same time, by adding aquatic plants such as water hyacinth and foxtail algae, not only the growth of moss is inhibited, but also the biodiversity of the water body is increased, promoting ecological balance. Regular water quality testing and maintenance ensure the continuous cleanliness of the water body, forming a virtuous circle, providing an effective solution for the long-term management of sedimentation tanks, and thus improving the overall ecological benefits. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative labor.

[0020] Figure 1 This is a process flow chart of the moss cleaning method provided in an embodiment of the present invention. DETAILED DESCRIPTION

[0021] The following will be combined with the drawings in the specification of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0022] It should be noted that the vertical flow sedimentation tank, also known as the vertical sedimentation tank, has a circular or square body plane. The wastewater it treats is discharged from the inlet pipe located in the center of the sedimentation tank from top to bottom. An umbrella-shaped baffle is set under the outlet of the inlet to make the wastewater evenly distributed in the tank, and then slowly rise along the entire cross-section of the tank; the suspended matter inside the vertical flow sedimentation tank will settle into the conical sludge hopper at the bottom of the tank under the action of gravity, and the clarified water will be discharged from the overflow weir around the upper end of the tank. In practical applications, scum troughs and baffles can also be set in front of the overflow weir to ensure the quality of the effluent. This setting method can make the sedimentation tank have a small footprint and a large depth, and the bottom of the tank is conical. The wastewater in the sedimentation tank flows vertically. The wastewater enters the tank from top to bottom through the inlet pipe located in the center of the tank (the flow rate in the pipe should be less than 30mm / s), and an umbrella-shaped baffle is set under the pipe to make the wastewater evenly distributed in the tank and then slowly rise along the entire water flow section (for domestic sewage, it is generally 0. 5~0.7mm / s, sedimentation time is 1~1.5h), suspended matter settles into the conical sludge hopper at the bottom of the pool, clarified water flows out from the pool along the peripheral overflow weir, baffles and scum troughs are set in front of the weir to intercept scum to ensure the quality of effluent water; one side of the sedimentation tank is equipped with a sludge discharge pipe (diameter greater than 200mm) against the pool wall to discharge the sludge regularly by hydrostatic pressure. It has the advantages of small footprint and easy sludge discharge, and is often used in sewage treatment plants with a water volume of less than 20000m3 / d.

[0023] It should also be noted that grey water, also known as reclaimed water, refers to sewage (waste) water that has been treated to meet the water quality standards and requirements for a certain purpose and can be reused; however, reclaimed water is not the same as grey water. The source of reclaimed water is more extensive, including domestic, industrial, and agricultural sewage, while the source of grey water usually refers specifically to drainage from buildings or building communities; it is called "reclaimed water" in sewage engineering and "reused water" in factories, and is generally distinguished by water quality. It mainly refers to non-drinking water that can be reused within a certain range after urban sewage or domestic sewage has been treated to meet certain water quality standards; water that has been deeply purified by urban sewage treatment facilities (including water that has been further treated after secondary treatment in sewage treatment plants and centralized treated water such as bathing water and vegetable washing water in large buildings and living communities) is collectively referred to as "grey water"; its water quality is between tap water (upstream water) and sewage (sewerage) discharged into pipes, so it is called "grey water", and the use of grey water is also called sewage reuse.

[0024] It is worth noting that suspended matter refers to organic and inorganic particles suspended in the water, that is, organic and inorganic particles that cannot pass through 0.45-micron filter paper or filters, such as silt, clay, organic matter, algae and microorganisms that are difficult to dissolve in water. Suspended matter refers to solid matter suspended in the water, including inorganic and organic matter that are insoluble in water, mud, clay, microorganisms, etc.; the content of suspended matter in water is one of the indicators to measure the degree of water pollution. Suspended matter is the main cause of water turbidity. The organic suspended matter in the water body is easily anaerobically fermented after deposition, causing the water quality to deteriorate; the suspended matter in the water is microparticles with a particle diameter of approximately 0.1μm-100μm, which can be seen by the naked eye. These microparticles are mainly composed of silt, clay, protozoa, algae, bacteria, viruses, and high-molecular organic matter.

[0025] Suspended solids or suspended colloids are divided into two major parts: organic and inorganic. Most of the organic part is debris particles, which are composed of carbohydrates (see carbohydrates), proteins (see proteins), lipids (see lipids), etc.; the inorganic part includes terrigenous mineral debris (such as quartz, feldspar, carbonates and clays), aquatic minerals (such as precipitated glauconite and philadelphite and other silicates, carbon); the particle size of suspended matter is generally between a few and a few hundred microns, and it is usually separated from seawater by a filter membrane with a pore size of 0.45 microns; suspended matter contains two types of organic components and inorganic components: (1) Organic components, mainly biological remains, excrement and decomposition products, composed of cellulose, starch and other carbohydrates, proteins, lipids and chitin; (2) Inorganic components, including quartz, feldspar, carbonates and clays from the continental mineral debris, silicates generated in the chemical process of seawater, etc. Example 1: Please refer to the attached Figure 1In this embodiment, after the sedimentation tank has been used for a long time, a large amount of moss will grow on the overflow weir of the sedimentation tank, and with the large amount of moss accumulation, a large amount of plankton will accumulate on the water surface of the sedimentation tank, affecting the sewage treatment effect; at the same time, the treatment of the moss requires staff to regularly and repeatedly clean it, which greatly reduces the sewage treatment efficiency; for this reason, this example pre-treats the moss on the sedimentation tank first, and after the pre-treatment, sprays the moss on the sedimentation tank to obtain a first sewage solution, which is a preliminary clarified solution of domestic wastewater after sedimentation treatment, mixed with suspended matter and hypochlorous acid solution; after the first preset time after the spraying ends, the hypochlorous acid can The method effectively inhibits moss, and after this period of time, the secondary sewage solution is irradiated with ultraviolet rays to obtain a second sewage solution, which is a primary clarified solution that is decomposed by light, and hypochlorous acid is decomposed at the same time, so that it can be mixed with suspended matter and moss residues to form a mid-level clarified solution; the second sewage solution is post-treated to obtain a third sewage solution, which is a clean clarified solution mixed with a variety of residual wastes after the mid-level clarified solution is post-treated; the third sewage solution is subjected to waste cleaning to obtain a clean water body, and the waste cleaning includes: timely collecting the moss residues generated during the cleaning process, and short-term isolation or physical filtration of the treated third sewage solution.

[0026] It should be noted that the specific processing methods include the following: 1. Pre-treat moss The moss is converted into a state that is easy to remove by physical and chemical methods; specifically, the moss is attached to the overflow weir of the sedimentation tank, and the pretreatment includes: converting the moss on the sedimentation tank into a state that is easy to remove by physical or chemical methods; the sedimentation tank is a vertical flow sedimentation tank, and the tank body plane is circular or square, and wastewater is discharged into the tank from top to bottom through an inlet pipe located in the center of the sedimentation tank.

[0027] 2. Spray treatment At a temperature range of 20°C to 30°C, the moss is sprayed with reclaimed water containing sodium hypochlorite; specifically, the spraying treatment comprises: at a temperature range of 20°C to 30°C, the reclaimed water containing sodium hypochlorite is sprayed corresponding to the overflow weir of the sedimentation tank, 3. Ultraviolet radiation irradiating the obtained first moss with ultraviolet rays; 4. Inhibit the growth of moss post-treating the second moss to inhibit its growth; 5. Clean up waste Clean up the moss residues, cleaning agents and other wastes generated during the cleaning process in a timely manner to avoid the residues affecting the water quality and prevent the moss from growing again; S501. Collect and treat the moss residues generated during the cleaning process in a timely manner to avoid the moss residues from polluting the water body again; S502. Short-term isolation or physical filtration of the treated water body to ensure that there is no moss residue and prevent the moss from growing again; 6. Evaluate the cleaning effect Regularly check the moss coverage in the sedimentation tank and evaluate the cleaning effect to ensure that the moss has been completely removed; if there is any residue, re-treat it, including the following steps: S601. Regularly use professional equipment or manual inspection to check the moss coverage in the sedimentation tank and evaluate the cleaning effect; S602. When it is found that the cleaning is incomplete, spray or ultraviolet irradiation is performed again to ensure the cleaning effect; 7. Restore the ecological balance of water bodies Use water quality regulators to adjust the pH value and dissolved oxygen concentration of the water body, restore the ecological balance of the water body, and create a suitable environment to inhibit the growth of moss; S701. Use appropriate water quality regulators to adjust the water quality according to the pH value and dissolved oxygen concentration of the water body to promote the ecological balance of the water body; S702. Ensure that the dissolved oxygen content in the water body is moderate by supplementing oxygen or adjusting the water flow to prevent the resurgence of moss 8. Regular maintenance Establish a regular inspection and maintenance mechanism to regularly detect, clean and prevent moss to ensure that the sedimentation tank remains clean for a long time and prevent moss from regrowing; the specific steps include: S801. Establish a monthly inspection and maintenance plan to regularly monitor the water quality changes and moss growth in the sedimentation tank; S802. Based on the monitoring results, timely cleaning or prevention and control measures shall be carried out to ensure that the sedimentation pond remains free of moss for a long time.

[0028] In addition, step S1 specifically includes the following steps: S101. Use a mechanical brush or a high-pressure water gun to preliminarily clean the moss on the inner wall and outer side of the overflow weir of the sedimentation tank to remove loose moss on the surface; S102, using an acidic or alkaline solution combined with a cleaning agent to adjust the pH value to a range suitable for moss removal, thereby promoting the rupture and shedding of moss cells.

[0029] The S2 step specifically includes the following steps: S201, spraying the sodium hypochlorite solution evenly on the surface of the moss, ensuring that each moss patch is evenly exposed to the solution; S202. The spraying time is controlled within 15 minutes to 30 minutes to ensure that the surface of the moss is fully chemically reacted to form the first moss.

[0030] In step S201, the sodium hypochlorite is prepared at a concentration of 0.1% to 0.5%.

[0031] The S3 step specifically includes the following steps: S301, keep the ultraviolet lamp about 30 cm to 50 cm away from the moss surface; S302, the irradiation time is controlled at 30 minutes to 60 minutes, and the sterilization effect of ultraviolet rays is used to destroy the cell structure and DNA inside the moss, and finally the second moss is obtained.

[0032] The wavelength of the ultraviolet lamp in step S301 is 200nm to 280nm.

[0033] The S4 step specifically includes the following steps: S401, use a specific concentration of biological inhibitor to spray evenly on the moss treatment area; S402. Reduce the nitrogen-phosphorus ratio in water bodies and regularly add aquatic plants with inhibitory effects to maintain the ecological balance of water bodies; S403. Regularly test and maintain water quality to ensure clean water and a suitable growth environment, thereby effectively inhibiting the regeneration of moss.

[0034] The biological inhibitor in step S401 specifically includes: one or more combinations of alginate, photosynthetic bacteria, and lactic acid bacteria.

[0035] The aquatic plants with inhibitory effects in step S402 include water hyacinth, foxtail, algae reed and cattail. Example

[0036] S1. Pretreatment of moss S101: Use a high pressure water gun to clean the inner wall and sides of the overflow weir of the sedimentation tank, removing 80% of the loose moss.

[0037] S102: Use an acidic cleaning agent with a pH of 4 to promote the rupture of moss cells.

[0038] S2. Spray treatment S201: Spray 0.3% sodium hypochlorite solution.

[0039] S202: The spraying time is controlled at 20 minutes.

[0040] S3. Ultraviolet irradiation S301: Keep the UV lamp 40cm away from the moss surface.

[0041] S302: The irradiation time is controlled at 45 minutes.

[0042] S4. Inhibit the growth of moss S401: Use of photosynthetic bacteria as bioinhibitors.

[0043] S402: Add water hyacinth to inhibit aquatic plants. Example 3 S1. Pretreatment of moss S101: Use a mechanical brush to clean the inner wall of the sedimentation tank and remove 70% of the moss.

[0044] S102: Using an alkaline solution with a pH of 8 to promote the shedding of moss cells.

[0045] S2. Spray treatment S201: Spray 0.2% sodium hypochlorite solution.

[0046] S202: The spraying time is controlled at 25 minutes.

[0047] S3. Ultraviolet irradiation S301: Keep the UV lamp 30cm away from the moss surface.

[0048] S302: The irradiation time is controlled at 30 minutes.

[0049] S4. Inhibit the growth of moss S401: Use of alginate as a bioinhibitor.

[0050] S402: Add cattail to inhibit aquatic plants. Example

[0051] S1. Pretreatment of moss S101: Use a high pressure water gun to clean the overflow weir of the sedimentation tank and remove 90% of the loose moss.

[0052] S102: Use a neutral pH cleaning agent to promote the rupture of moss cells.

[0053] S2. Spray treatment S201: Spray 0.4% sodium hypochlorite solution.

[0054] S202: The spraying time is controlled at 15 minutes.

[0055] S3. Ultraviolet irradiation S301: Keep the UV lamp 50cm away from the moss surface.

[0056] S302: The irradiation time is controlled at 60 minutes.

[0057] S4. Inhibit the growth of moss S401: Use of lactic acid bacteria as bio-inhibitors.

[0058] S402: Add foxtail to inhibit aquatic plants. Example

[0059] S1. Pretreatment of moss S101: A combination of mechanical brush and high-pressure water gun removes 85% of moss.

[0060] S102: Use a cleaning agent with a pH of 6 to promote the shedding of moss cells.

[0061] S2. Spray treatment S201: Spray 0.1% sodium hypochlorite solution.

[0062] S202: The spraying time is controlled at 30 minutes.

[0063] S3. Ultraviolet irradiation S301: Keep the UV lamp 35cm away from the moss surface.

[0064] S302: The irradiation time is controlled at 50 minutes.

[0065] S4. Inhibit the growth of moss S401: Use of a combination of alginate and photosynthetic bacteria as bioinhibitors.

[0066] S402: Add algae reed to inhibit aquatic plants.

[0067] Table 1: Summary of implementation results.

[0068] Example Cleaning effect (%) Sodium hypochlorite concentration (%) Spraying time (minutes) UV exposure time (minutes) Biological inhibitors Aquatic plants Example 2 80 0.3 20 45 Photosynthetic bacteria Water hyacinth Example 3 70 0.2 25 30 Alginate cat-tail Example 4 90 0.4 15 60 Lactic acid bacteria Foxtail Example 5 85 0.1 30 50 Alginate + photosynthetic bacteria Phragmites australis Table 1; Conclusion: From Table 1, we can see that: Cleaning effect: The initial cleaning effect (percentage of moss removed) of different embodiments fluctuated between 70% and 90%, indicating the effectiveness of physical and chemical pretreatment. Higher cleaning effects are usually associated with stronger physical cleaning means (such as high-pressure water guns or mechanical brushes).

[0069] Sodium hypochlorite concentration: The sodium hypochlorite concentration of all examples was between 0.1% and 0.4%, showing that chemical cleaning can still be effective at lower concentrations. The application of higher concentrations (such as 0.4%) is usually combined with shorter spraying time to achieve ideal cleaning results.

[0070] Spraying time: The spraying time should be controlled within 15 to 30 minutes. Long-term spraying can enhance the contact between moss and chemical solution, promote chemical reaction, and thus improve cleaning efficiency.

[0071] Ultraviolet irradiation: The choice of ultraviolet irradiation time (30 to 60 minutes) directly affects the cell destruction effect of moss. A longer irradiation time can kill moss cells more effectively. At the same time, ultraviolet irradiation can partially decompose hypochlorous acid, avoiding the need for secondary treatment of hypochlorous acid.

[0072] Bioinhibitors and Aquatic Plants: The bioinhibitors (e.g., photosynthetic bacteria, alginate, lactic acid bacteria) and aquatic plants (e.g., water hyacinth, cattail, foxtail, algae reed) used in different examples are diverse, demonstrating flexibility and adaptability in inhibiting the growth of mosses.

[0073] In summary: The present invention forms a multi-level moss cleaning mechanism through four systematic steps, including pretreatment, spray treatment, ultraviolet irradiation and biological inhibition. Through a combination of physical and chemical methods, the loose moss in the sedimentation tank is first effectively removed, and then the moss is sprayed with a solution containing sodium hypochlorite to ensure that each moss patch is evenly contacted to achieve an ideal chemical cleaning effect. In addition, ultraviolet irradiation further destroys the structure of moss cells and enhances the removal effect. Ultimately, this series of treatments can not only significantly reduce the biomass of moss, but also increase the light transmittance and oxygen content of the water body, thereby improving water quality and promoting the healthy development of the water ecology.

[0074] Example 3 In this embodiment, in order to specifically implement the above steps, the second sewage solution is post-treated, including: By using a specific concentration of biological inhibitors to evenly spray on the moss treatment area of ​​the overflow weir, the nitrogen-phosphorus ratio of the water body is reduced, and after a third preset period of time, aquatic plants with inhibitory effects are added to further effectively biologically treat the sewage and improve the quality of sewage treatment.

[0075] At the same time, after step S5, in order to reduce the number of steps, step S6 is further included, and step S6 includes: After the second preset time, the thickness of the moss on the overflow weir is detected, wherein the moss thickness is the length of the moss growing on the overflow weir, and the reference thickness is determined by an empirical value. Under normal circumstances, due to the inhibitory effect of hypochlorous acid, the moss growth is often not too fast; if the moss thickness is greater than the reference thickness, reprocessing is performed; The re-treatment includes using professional equipment or manually checking the moss coverage on the overflow weir to determine the moss coverage rate. When the moss coverage rate is greater than 30%, spraying or ultraviolet irradiation is performed again; wherein the moss coverage rate refers to the ratio of the area occupied by moss growing and covering the overflow weir of the sedimentation tank.

[0076] In addition, after step S6, step S7 is also included, and step S7 includes the following steps: Use water quality regulators to adjust the pH value and dissolved oxygen concentration of water bodies; According to the pH value and dissolved oxygen concentration of the water body, ensure that the dissolved oxygen content in the water body is moderate by supplementing oxygen or adjusting the water flow, and establish a regular inspection and maintenance mechanism to regularly detect, clean and prevent moss.

[0077] A mechanical brush or a high-pressure water gun is used to preliminarily clean the area around and the outer wall of the overflow weir to remove loose moss on the surface; the chemical method includes: using an acidic or alkaline solution combined with a cleaning agent to adjust the pH value until it is adjusted to a range suitable for moss removal, thereby promoting the rupture and shedding of moss cells, effectively clearing the moss, and achieving the purpose of sewage treatment.

[0078] The above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit the same. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that the technical solutions described in the aforementioned embodiments may still be modified, or some of the technical features may be replaced by equivalents. However, these modifications or replacements do not deviate the essence of the corresponding technical solutions from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. A method for cleaning moss in a sedimentation tank, characterized in that: The following steps are involved: S1. Pre-treating the moss on the sedimentation tank, wherein the moss is attached to the overflow weir of the sedimentation tank, and the pre-treating comprises: converting the moss on the sedimentation tank into a state that is easy to remove by a physical method or a chemical method; the sedimentation tank is a vertical flow sedimentation tank, the plane of the tank body is circular or square, and the wastewater is discharged into the tank from top to bottom through a water inlet pipe arranged in the center of the sedimentation tank; S2. After the pretreatment, spraying the moss on the sedimentation tank, wherein the spraying treatment comprises: spraying the overflow weir of the sedimentation tank with reclaimed water containing sodium hypochlorite at a temperature range of 20° C. to obtain a first sewage solution, wherein the first sewage solution is a primary clarified solution of domestic wastewater after sedimentation treatment, mixed with suspended matter and hypochlorous acid solution; S3, after the first preset time period after the spraying ends, the secondary sewage solution is subjected to ultraviolet irradiation to obtain a second sewage solution, wherein the second sewage solution is a secondary clarified solution mixed with suspended matter and moss residue after the primary clarified solution is decomposed by light; S4, post-treating the second sewage solution to obtain a third sewage solution, wherein the third sewage solution is a clean clarified solution mixed with a variety of residual wastes after post-treatment of the intermediate clarified solution; S5. Cleaning the third sewage solution to obtain clean water. The cleaning includes timely collecting moss residues generated during the cleaning process and isolating or physically filtering the treated third sewage solution for a short period of time.

2. The moss cleaning method according to claim 1, characterized in that: The physical method includes: using a mechanical brush or a high-pressure water gun to preliminarily clean the area around and the outer wall of the overflow weir to remove loose moss on the surface; the chemical method includes: using an acidic or alkaline solution combined with a cleaning agent to adjust the pH value until it is adjusted to a range suitable for moss removal, thereby promoting the rupture and shedding of moss cells.

3. The moss cleaning method according to claim 1, characterized in that: The method of using the reclaimed water containing sodium hypochlorite to spray the edge of the sedimentation tank includes the following steps: The intermediate water containing the sodium hypochlorite solution is sequentially and rotationally sprayed on the surface of the overflow weir along one of the starting points of the overflow weir; wherein the spraying time is controlled within 15 minutes to 30 minutes.

4. The moss cleaning method according to claim 1, characterized in that: The sodium hypochlorite preparation concentration of the sodium hypochlorite-containing reclaimed water is 0.1% to 0.5%.

5. The moss cleaning method according to claim 1, characterized in that: The step of subjecting the secondary sewage solution to ultraviolet irradiation comprises: The ultraviolet lamp is kept about 30 cm to 50 cm away from the moss surface, wherein the irradiation time of the ultraviolet lamp is controlled at 30 min to 60 min, and the wavelength of the ultraviolet lamp is 200 nm to 280 nm.

6. A method for cleaning moss in a sedimentation pond according to claim 1, characterized in that: The post-processing of the second sewage solution comprises: A biological inhibitor of a specific concentration is uniformly sprayed on the moss treatment area of ​​the overflow weir, and the nitrogen-phosphorus ratio of the water body is reduced. After a third preset time period, aquatic plants with inhibitory effects are added.

7. The moss cleaning method according to claim 6, characterized in that: The biological inhibitor includes any one or more of the following: alginate, photosynthetic bacteria and lactic acid bacteria; the aquatic plants include any one or more of the following: water hyacinth, foxtail, algae reed and cattail.

8. The moss cleaning method according to claim 1, characterized in that: After step S5, step S6 is further included, and step S6 includes: After a second preset time, detecting the thickness of the moss on the overflow weir, and performing reprocessing if the thickness of the moss is greater than a reference thickness; The re-treatment includes using professional equipment or manually checking the moss coverage on the overflow weir to determine the moss coverage rate. When the moss coverage rate is greater than 30%, spraying or ultraviolet irradiation is performed again; wherein the moss coverage rate refers to the ratio of the area occupied by moss growing and covering the overflow weir of the sedimentation tank.

9. The moss cleaning method according to claim 8, characterized in that: After step S6, step S7 is further included, and step S7 includes the following steps: Use water quality regulators to adjust the pH value and dissolved oxygen concentration of water bodies; According to the pH value and dissolved oxygen concentration of the water body, ensure that the dissolved oxygen content in the water body is moderate by supplementing oxygen or adjusting the water flow, and establish a regular inspection and maintenance mechanism to regularly detect, clean and prevent moss.

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